Cancer in its many forms is uncontrolled growth of abnormal cells in the body. There are immune cells in a patient's blood, which, in general, are white blood cells (WBC) including, for example, dendritic cells, antigen presenting cells (APC's), and effector cells. Enhancing the growth or effectiveness of immune cells in a patient being treated for cancer is highly desirable.
Cancerous cells are frequently referred to as malignant cells and often form tumors. Symptoms of cancer depend on the type and location of the tumor. Various anti-cancer substances having the potential to suppress the cancer's growth or destroy cancer cells are injected into a cancer patient. For example, biotech companies have developed antibodies that attach to effector cells or other targets within a patient's blood or areas accessible to the blood stream that may result in the regression of the cancer, or at least suppression of its growth. These antibodies may act by different mechanisms, such as by attaching to growth factors, or their receptors, and interfering with growth signals. Such mechanisms may also operate by prohibiting new blood vessel growth into the tumor. Other antibodies attach to various antigens on tumor cells, and are believed to operate by allowing effector cells to localize to the tumor cells and destroy them.
Attachment of antibodies to effector cells, however, does not always lead to immediate and complete termination of the cancerous growth or provoke an immune response from the patient. Nevertheless, such attachment is desirable because anti-tumor activity on the part of effector cells is conducted by such attachment of the antibodies. Other anti-cancer substances beside antibodies may interact with a patient's effector cells to provoke an immune response, whether or not any specific antibody attachment occurs. An example of this is interferon, which is known to stimulate effector cells against cancer. Immune responses may be different with different types of cancers, and conceivably in the same tumor type in different patients. Provoking an immune response is a way to enable the patient's own immune system to suppress the growth of the cancer.